Medium
S.53 on Heatline CaprizPlus 24a

Your boiler has noticed that water is not circulating through your radiators fast enough, causing it to throttle its power to prevent overheating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Waiting cycle: temperature differential between heating fl ow and return is too high. If ∆T > 30, forcing to Pmin

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We could not tie this code to a specific manual. Treat it as indicative only.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check that all radiator valves (TRVs) are fully openEnsure the boiler pressure is between 1.0 and 1.5 bar on the gaugeBleed all radiators to remove trapped air bubbles

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Related fault codes

F.22View →F.23View →F.24View →

All 111 fault codes on the CaprizPlus 24a

Seeing a different code? Every code this model can display, in one place.

d.00d.01d.02d.08d.09d.10d.16d.17d.18d.20d.22d.23d.33d.34d.35d.36d.40d.41d.44d.67d.68d.69d.71d.80d.81d.82d.83d.85d.93d.94d.96ErrF00F01F10F11F20F22F23F24F26F27F28F29F32F49F61F62F63F64F65F67F68F70F71F72F73F74F76F77F83F84F85F86P.01P.02P.03P.05P.06P.07S.00S.01S.02S.03S.04S.05S.06S.07S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.35S.36S.37S.41S.54S.58S.90S.92S.95S.96S.97S.98

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